Fiber optic communication systems are becoming prevalent in part because service providers want to deliver high band width communication capabilities to customers. Fiber optic communication systems employ a network of fiber optic cables to transmit large volumes of data and voice signals over relatively long distances. A typical fiber optic network includes a system of fiber optic cables that interconnect a plurality of subscribers (also known as end users or customers) to a central location such as a central office. The system of fiber optic cables can include architecture that transitions from higher fiber count fiber optic cables (e.g., distribution cables, trunk cables, main cables, F1 cables, etc.) to lower fiber count fiber optic cables. The smallest fiber count cables (e.g., drop cables) are typically nearest to the subscribers. Enclosures (e.g., drop terminals, splice closures, optical network terminals, pedestals, aerial enclosures, etc.) are provided throughout the network for providing connection locations for interconnecting higher fiber count fiber optic cables to lower fiber count fiber optic cables.
Enclosures also can be used to house optical splitting components such as optical signal power splitters and wavelength division multiplexers/splitters. An optical splitting component is used to increase the subscriber capacity of a given network by optically connecting an optical fiber routed to the central office to a plurality of optical fibers that can be routed to separate subscriber locations. This “one-to-many” connection increases the subscriber capacity of the network.
Optical signal power splitters are capable of splitting an entire optical signal carried by one optical fiber to two or more optical fibers (e.g., 1 by 2 splitters; 1 by 4 splitters; 1 by 8 splitters, 1 by 16 splitters; 1 by 32 splitters, etc.), and are also capable of combining optical signals from multiple optical fibers back to one optical fiber. Wavelength splitting/dividing structures (e.g., coarse wavelength dividing multiplexers and de-multiplexers, dense wavelength dividing multiplexers and de-multiplexers, array waveguide grading structures, etc.) are capable dividing an optical signal carried by one optical fiber into separate wavelength ranges with each range then being directed to and carried by a separate optical fiber, and are also capable of combining separate wavelength ranges carried by separate optical fibers back to one optical fiber.
The performance of a fiber optic communication system is negatively affected by return loss. Return loss is the loss of signal power caused by optical reflection that occurs along a given optical transmission path. It is desirable to reduce return loss.